Sol Defense Group 3/A-5 is a Battle Group of the UNSC Navy. The only information pertaining to this unit comes from the Halo: Arms Race promotional Halo 3 video released on June 10, 2007. The group was likely engaged in combat with the Covenant in the Battle of Earth, as the video's visible factual text says the group only has 2 ships out of 8 remaining. The group requested rearmament since its readiness level was critical. Misriah armory factories on Mars then were shown mass-producing equipment for the Battle Group, which likely not only uses its ships for space combat, but also assists Marines in ground engagements since the production of Marine vehicles (Warthogs and Pelicans) and weapons (Sniper Rifles, Battle Rifles, and M6G Magnum Sidearms) are shown.